公开(公告)号：CA1067676A

公开(公告)日：1979-12-11

申请号：CA233469

申请日：1975-08-14

Applicant: BASF AG

Inventor： VOELKL ERFRIED ,  SCHREINER SIEGFRIED ,  WUNSCH GERD ,  KIENER VOLKER ,  WAIBEL RUDI ,  KOESTER HARTWIG

IPC: C01B31/26 ,  C01B17/66 ,  C01D5/00

Abstract: For the preparation of anhydrous sodium dithionite by the reaction of sulfur dioxide with sodium formate and caustic soda in the presence of organic solvents, sulfur dioxide is passed, together with the formate, into a liquid containing all of the caustic soda required for the reaction. This initial liquid may contain, in addition to the caustic soda, a portion of the sulfur dioxide or formate required for the reaction. This process gives high yields of sodium dithionite at constant purity and cristal size of the product in a simpler procedure of an industrially more practicable nature without these results being subject to undue fluctuations of an uncontrollable kind.